Prune tongue is not necessarily scarlet fever, but may be associated with other diseases such as Kawasaki disease, typhoid myocarditis, paratyphoid fever and rotavirus infection. Prune Tongue is a pathological feature of congested and edematous papillae of the tongue caused by certain congestive disorders, which are raised, thickened and reddish, and the tongue coating is whitish and resembles that of a prune. If prune tongue is caused by scarlet fever, the patient may also have mild sore throat and fever; some patients may have a rash on the skin surface, but it is rare and usually resolves within a short period of time. The incubation period of the disease is usually about 1 to 12 days, and the symptoms are mostly not obvious in the early stage. In addition to scarlet fever, Kawasaki disease, typhoid myocarditis, paratyphoid fever, and rotavirus infections can also cause this symptom to appear. Therefore, it is recommended to consult a doctor as soon as possible in case of prune tongue, and then diagnose and analyze the disease through serological and routine blood tests, and then standardize the treatment under the guidance of a professional doctor after the diagnosis is confirmed, so as to avoid delaying the disease.